1. Field of the Invention
This invention relates generally to pneumatic tools and in particular to operating valves for such tools.
2. Description of the Prior Art
The motors of many tools are pneumatically controlled. Tip valves for restricting and controlling the air flow for these pneumatic tools have previously been provided. As seen in FIG. 2, these prior art valves include a valve seat having a bore (to allow air flow therethrough) with a central axis and a second valve member having an engaging surface biased against the valve seat to form a substantially fluid-tight seal and a stem coupled to the second valve member and coaxially disposed through the bore in the normal closed position. The stem is coupled to a trigger mechanism for opening and closing the valve. Depressing of the trigger tilts or tips the stem and the engaging surface away from the valve seat.
This tipping allows air flow through the bore of the valve seat. However, the constraints of the cylinder in which the second valve member sits does not allow the second valve member to tip far enough so that it does not impede air flow and allows maximum flow through the bore to efficiently operate the pneumatic motor.
Attempts to solve this problem have simply included enlarging the second valve member and bore therethrough. This solution, however, results in the widening the handle of the tool which surrounds the valve seat, making the handle too large and cumbersome to use comfortably.